SemaDecl.cpp revision c1cc6dccd42b91a2ebb397415940da91dbf36103
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/ASTConsumer.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/Attr.h" 18#include "clang/AST/Builtins.h" 19#include "clang/AST/Decl.h" 20#include "clang/AST/Expr.h" 21#include "clang/AST/Type.h" 22#include "clang/Parse/DeclSpec.h" 23#include "clang/Parse/Scope.h" 24#include "clang/Basic/LangOptions.h" 25#include "clang/Basic/TargetInfo.h" 26#include "clang/Basic/SourceManager.h" 27#include "clang/AST/ExprCXX.h" 28// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 29#include "clang/Lex/Preprocessor.h" 30#include "clang/Lex/HeaderSearch.h" 31#include "llvm/ADT/SmallString.h" 32#include "llvm/ADT/SmallSet.h" 33#include "llvm/ADT/DenseSet.h" 34using namespace clang; 35 36Sema::DeclTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 37 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 38 39 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 40 isa<ObjCInterfaceDecl>(IIDecl) || 41 isa<TagDecl>(IIDecl))) 42 return IIDecl; 43 return 0; 44} 45 46void Sema::PushDeclContext(DeclContext *DC) { 47 assert( ( (isa<ObjCMethodDecl>(DC) && isa<TranslationUnitDecl>(CurContext)) 48 || DC->getParent() == CurContext ) && 49 "The next DeclContext should be directly contained in the current one."); 50 CurContext = DC; 51} 52 53void Sema::PopDeclContext() { 54 assert(CurContext && "DeclContext imbalance!"); 55 // If CurContext is a ObjC method, getParent() will return NULL. 56 CurContext = isa<ObjCMethodDecl>(CurContext) 57 ? Context.getTranslationUnitDecl() 58 : CurContext->getParent(); 59} 60 61/// Add this decl to the scope shadowed decl chains. 62void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 63 S->AddDecl(D); 64 65 // C++ [basic.scope]p4: 66 // -- exactly one declaration shall declare a class name or 67 // enumeration name that is not a typedef name and the other 68 // declarations shall all refer to the same object or 69 // enumerator, or all refer to functions and function templates; 70 // in this case the class name or enumeration name is hidden. 71 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 72 // We are pushing the name of a tag (enum or class). 73 IdentifierResolver::ctx_iterator 74 CIT = IdResolver.ctx_begin(TD->getIdentifier(), TD->getDeclContext()); 75 if (CIT != IdResolver.ctx_end(TD->getIdentifier()) && 76 IdResolver.isDeclInScope(*CIT, TD->getDeclContext(), S)) { 77 // There is already a declaration with the same name in the same 78 // scope. It must be found before we find the new declaration, 79 // so swap the order on the shadowed declaration chain. 80 81 IdResolver.AddShadowedDecl(TD, *CIT); 82 return; 83 } 84 } 85 86 IdResolver.AddDecl(D); 87} 88 89void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 90 if (S->decl_empty()) return; 91 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 92 93 // We only want to remove the decls from the identifier decl chains for local 94 // scopes, when inside a function/method. 95 if (S->getFnParent() == 0) 96 return; 97 98 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 99 I != E; ++I) { 100 Decl *TmpD = static_cast<Decl*>(*I); 101 assert(TmpD && "This decl didn't get pushed??"); 102 ScopedDecl *D = dyn_cast<ScopedDecl>(TmpD); 103 assert(D && "This decl isn't a ScopedDecl?"); 104 105 IdentifierInfo *II = D->getIdentifier(); 106 if (!II) continue; 107 108 // Unlink this decl from the identifier. 109 IdResolver.RemoveDecl(D); 110 111 // This will have to be revisited for C++: there we want to nest stuff in 112 // namespace decls etc. Even for C, we might want a top-level translation 113 // unit decl or something. 114 if (!CurFunctionDecl) 115 continue; 116 117 // Chain this decl to the containing function, it now owns the memory for 118 // the decl. 119 D->setNext(CurFunctionDecl->getDeclChain()); 120 CurFunctionDecl->setDeclChain(D); 121 } 122} 123 124/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 125/// return 0 if one not found. 126ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 127 // The third "scope" argument is 0 since we aren't enabling lazy built-in 128 // creation from this context. 129 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 130 131 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 132} 133 134/// LookupDecl - Look up the inner-most declaration in the specified 135/// namespace. 136Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 137 Scope *S, bool enableLazyBuiltinCreation) { 138 if (II == 0) return 0; 139 unsigned NS = NSI; 140 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 141 NS |= Decl::IDNS_Tag; 142 143 // Scan up the scope chain looking for a decl that matches this identifier 144 // that is in the appropriate namespace. This search should not take long, as 145 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 146 for (IdentifierResolver::iterator 147 I = IdResolver.begin(II, CurContext), E = IdResolver.end(II); I != E; ++I) 148 if ((*I)->getIdentifierNamespace() & NS) 149 return *I; 150 151 // If we didn't find a use of this identifier, and if the identifier 152 // corresponds to a compiler builtin, create the decl object for the builtin 153 // now, injecting it into translation unit scope, and return it. 154 if (NS & Decl::IDNS_Ordinary) { 155 if (enableLazyBuiltinCreation) { 156 // If this is a builtin on this (or all) targets, create the decl. 157 if (unsigned BuiltinID = II->getBuiltinID()) 158 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 159 } 160 if (getLangOptions().ObjC1) { 161 // @interface and @compatibility_alias introduce typedef-like names. 162 // Unlike typedef's, they can only be introduced at file-scope (and are 163 // therefore not scoped decls). They can, however, be shadowed by 164 // other names in IDNS_Ordinary. 165 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 166 if (IDI != ObjCInterfaceDecls.end()) 167 return IDI->second; 168 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 169 if (I != ObjCAliasDecls.end()) 170 return I->second->getClassInterface(); 171 } 172 } 173 return 0; 174} 175 176void Sema::InitBuiltinVaListType() { 177 if (!Context.getBuiltinVaListType().isNull()) 178 return; 179 180 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 181 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 182 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 183 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 184} 185 186/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 187/// lazily create a decl for it. 188ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 189 Scope *S) { 190 Builtin::ID BID = (Builtin::ID)bid; 191 192 if (BID == Builtin::BI__builtin_va_start || 193 BID == Builtin::BI__builtin_va_copy || 194 BID == Builtin::BI__builtin_va_end) 195 InitBuiltinVaListType(); 196 197 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 198 FunctionDecl *New = FunctionDecl::Create(Context, 199 Context.getTranslationUnitDecl(), 200 SourceLocation(), II, R, 201 FunctionDecl::Extern, false, 0); 202 203 // Create Decl objects for each parameter, adding them to the 204 // FunctionDecl. 205 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 206 llvm::SmallVector<ParmVarDecl*, 16> Params; 207 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 208 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 209 FT->getArgType(i), VarDecl::None, 0, 210 0)); 211 New->setParams(&Params[0], Params.size()); 212 } 213 214 215 216 // TUScope is the translation-unit scope to insert this function into. 217 PushOnScopeChains(New, TUScope); 218 return New; 219} 220 221/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 222/// and scope as a previous declaration 'Old'. Figure out how to resolve this 223/// situation, merging decls or emitting diagnostics as appropriate. 224/// 225TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 226 // Verify the old decl was also a typedef. 227 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 228 if (!Old) { 229 Diag(New->getLocation(), diag::err_redefinition_different_kind, 230 New->getName()); 231 Diag(OldD->getLocation(), diag::err_previous_definition); 232 return New; 233 } 234 235 // Allow multiple definitions for ObjC built-in typedefs. 236 // FIXME: Verify the underlying types are equivalent! 237 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 238 return Old; 239 240 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 241 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 242 // *either* declaration is in a system header. The code below implements 243 // this adhoc compatibility rule. FIXME: The following code will not 244 // work properly when compiling ".i" files (containing preprocessed output). 245 SourceManager &SrcMgr = Context.getSourceManager(); 246 const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); 247 const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); 248 HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); 249 DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); 250 DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); 251 252 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 253 if ((OldDirType != DirectoryLookup::NormalHeaderDir || 254 NewDirType != DirectoryLookup::NormalHeaderDir) || 255 getLangOptions().Microsoft) 256 return New; 257 258 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 259 // TODO: This is totally simplistic. It should handle merging functions 260 // together etc, merging extern int X; int X; ... 261 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 262 Diag(Old->getLocation(), diag::err_previous_definition); 263 return New; 264} 265 266/// DeclhasAttr - returns true if decl Declaration already has the target attribute. 267static bool DeclHasAttr(const Decl *decl, const Attr *target) { 268 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 269 if (attr->getKind() == target->getKind()) 270 return true; 271 272 return false; 273} 274 275/// MergeAttributes - append attributes from the Old decl to the New one. 276static void MergeAttributes(Decl *New, Decl *Old) { 277 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 278 279// FIXME: fix this code to cleanup the Old attrs correctly 280 while (attr) { 281 tmp = attr; 282 attr = attr->getNext(); 283 284 if (!DeclHasAttr(New, tmp)) { 285 New->addAttr(tmp); 286 } else { 287 tmp->setNext(0); 288 delete(tmp); 289 } 290 } 291} 292 293/// MergeFunctionDecl - We just parsed a function 'New' from 294/// declarator D which has the same name and scope as a previous 295/// declaration 'Old'. Figure out how to resolve this situation, 296/// merging decls or emitting diagnostics as appropriate. 297/// Redeclaration will be set true if thisNew is a redeclaration OldD. 298FunctionDecl * 299Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 300 Redeclaration = false; 301 // Verify the old decl was also a function. 302 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 303 if (!Old) { 304 Diag(New->getLocation(), diag::err_redefinition_different_kind, 305 New->getName()); 306 Diag(OldD->getLocation(), diag::err_previous_definition); 307 return New; 308 } 309 310 QualType OldQType = Context.getCanonicalType(Old->getType()); 311 QualType NewQType = Context.getCanonicalType(New->getType()); 312 313 // C++ [dcl.fct]p3: 314 // All declarations for a function shall agree exactly in both the 315 // return type and the parameter-type-list. 316 if (getLangOptions().CPlusPlus && OldQType == NewQType) { 317 MergeAttributes(New, Old); 318 Redeclaration = true; 319 return MergeCXXFunctionDecl(New, Old); 320 } 321 322 // C: Function types need to be compatible, not identical. This handles 323 // duplicate function decls like "void f(int); void f(enum X);" properly. 324 if (!getLangOptions().CPlusPlus && 325 Context.functionTypesAreCompatible(OldQType, NewQType)) { 326 MergeAttributes(New, Old); 327 Redeclaration = true; 328 return New; 329 } 330 331 // A function that has already been declared has been redeclared or defined 332 // with a different type- show appropriate diagnostic 333 diag::kind PrevDiag; 334 if (Old->isThisDeclarationADefinition()) 335 PrevDiag = diag::err_previous_definition; 336 else if (Old->isImplicit()) 337 PrevDiag = diag::err_previous_implicit_declaration; 338 else 339 PrevDiag = diag::err_previous_declaration; 340 341 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 342 // TODO: This is totally simplistic. It should handle merging functions 343 // together etc, merging extern int X; int X; ... 344 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 345 Diag(Old->getLocation(), PrevDiag); 346 return New; 347} 348 349/// equivalentArrayTypes - Used to determine whether two array types are 350/// equivalent. 351/// We need to check this explicitly as an incomplete array definition is 352/// considered a VariableArrayType, so will not match a complete array 353/// definition that would be otherwise equivalent. 354static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 355 const ArrayType *NewAT = NewQType->getAsArrayType(); 356 const ArrayType *OldAT = OldQType->getAsArrayType(); 357 358 if (!NewAT || !OldAT) 359 return false; 360 361 // If either (or both) array types in incomplete we need to strip off the 362 // outer VariableArrayType. Once the outer VAT is removed the remaining 363 // types must be identical if the array types are to be considered 364 // equivalent. 365 // eg. int[][1] and int[1][1] become 366 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 367 // removing the outermost VAT gives 368 // CAT(1, int) and CAT(1, int) 369 // which are equal, therefore the array types are equivalent. 370 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 371 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 372 return false; 373 NewQType = NewAT->getElementType().getCanonicalType(); 374 OldQType = OldAT->getElementType().getCanonicalType(); 375 } 376 377 return NewQType == OldQType; 378} 379 380/// MergeVarDecl - We just parsed a variable 'New' which has the same name 381/// and scope as a previous declaration 'Old'. Figure out how to resolve this 382/// situation, merging decls or emitting diagnostics as appropriate. 383/// 384/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 385/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 386/// 387VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 388 // Verify the old decl was also a variable. 389 VarDecl *Old = dyn_cast<VarDecl>(OldD); 390 if (!Old) { 391 Diag(New->getLocation(), diag::err_redefinition_different_kind, 392 New->getName()); 393 Diag(OldD->getLocation(), diag::err_previous_definition); 394 return New; 395 } 396 397 MergeAttributes(New, Old); 398 399 // Verify the types match. 400 QualType OldCType = Context.getCanonicalType(Old->getType()); 401 QualType NewCType = Context.getCanonicalType(New->getType()); 402 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 403 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 404 Diag(Old->getLocation(), diag::err_previous_definition); 405 return New; 406 } 407 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 408 if (New->getStorageClass() == VarDecl::Static && 409 (Old->getStorageClass() == VarDecl::None || 410 Old->getStorageClass() == VarDecl::Extern)) { 411 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 412 Diag(Old->getLocation(), diag::err_previous_definition); 413 return New; 414 } 415 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 416 if (New->getStorageClass() != VarDecl::Static && 417 Old->getStorageClass() == VarDecl::Static) { 418 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 419 Diag(Old->getLocation(), diag::err_previous_definition); 420 return New; 421 } 422 // We've verified the types match, now handle "tentative" definitions. 423 if (Old->isFileVarDecl() && New->isFileVarDecl()) { 424 // Handle C "tentative" external object definitions (C99 6.9.2). 425 bool OldIsTentative = false; 426 bool NewIsTentative = false; 427 428 if (!Old->getInit() && 429 (Old->getStorageClass() == VarDecl::None || 430 Old->getStorageClass() == VarDecl::Static)) 431 OldIsTentative = true; 432 433 // FIXME: this check doesn't work (since the initializer hasn't been 434 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 435 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 436 // thrown out the old decl. 437 if (!New->getInit() && 438 (New->getStorageClass() == VarDecl::None || 439 New->getStorageClass() == VarDecl::Static)) 440 ; // change to NewIsTentative = true; once the code is moved. 441 442 if (NewIsTentative || OldIsTentative) 443 return New; 444 } 445 // Handle __private_extern__ just like extern. 446 if (Old->getStorageClass() != VarDecl::Extern && 447 Old->getStorageClass() != VarDecl::PrivateExtern && 448 New->getStorageClass() != VarDecl::Extern && 449 New->getStorageClass() != VarDecl::PrivateExtern) { 450 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 451 Diag(Old->getLocation(), diag::err_previous_definition); 452 } 453 return New; 454} 455 456/// CheckParmsForFunctionDef - Check that the parameters of the given 457/// function are appropriate for the definition of a function. This 458/// takes care of any checks that cannot be performed on the 459/// declaration itself, e.g., that the types of each of the function 460/// parameters are complete. 461bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 462 bool HasInvalidParm = false; 463 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 464 ParmVarDecl *Param = FD->getParamDecl(p); 465 466 // C99 6.7.5.3p4: the parameters in a parameter type list in a 467 // function declarator that is part of a function definition of 468 // that function shall not have incomplete type. 469 if (Param->getType()->isIncompleteType() && 470 !Param->isInvalidDecl()) { 471 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 472 Param->getType().getAsString()); 473 Param->setInvalidDecl(); 474 HasInvalidParm = true; 475 } 476 } 477 478 return HasInvalidParm; 479} 480 481/// CreateImplicitParameter - Creates an implicit function parameter 482/// in the scope S and with the given type. This routine is used, for 483/// example, to create the implicit "self" parameter in an Objective-C 484/// method. 485ParmVarDecl * 486Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 487 SourceLocation IdLoc, QualType Type) { 488 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, IdLoc, Id, Type, 489 VarDecl::None, 0, 0); 490 if (Id) 491 PushOnScopeChains(New, S); 492 493 return New; 494} 495 496/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 497/// no declarator (e.g. "struct foo;") is parsed. 498Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 499 // TODO: emit error on 'int;' or 'const enum foo;'. 500 // TODO: emit error on 'typedef int;' 501 // if (!DS.isMissingDeclaratorOk()) Diag(...); 502 503 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 504} 505 506bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 507 // Get the type before calling CheckSingleAssignmentConstraints(), since 508 // it can promote the expression. 509 QualType InitType = Init->getType(); 510 511 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 512 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 513 InitType, Init, "initializing"); 514} 515 516bool Sema::CheckInitExpr(Expr *expr, InitListExpr *IList, unsigned slot, 517 QualType ElementType) { 518 Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. 519 if (CheckSingleInitializer(expr, ElementType)) 520 return true; // types weren't compatible. 521 522 if (savExpr != expr) // The type was promoted, update initializer list. 523 IList->setInit(slot, expr); 524 return false; 525} 526 527bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 528 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 529 // C99 6.7.8p14. We have an array of character type with unknown size 530 // being initialized to a string literal. 531 llvm::APSInt ConstVal(32); 532 ConstVal = strLiteral->getByteLength() + 1; 533 // Return a new array type (C99 6.7.8p22). 534 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 535 ArrayType::Normal, 0); 536 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 537 // C99 6.7.8p14. We have an array of character type with known size. 538 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 539 Diag(strLiteral->getSourceRange().getBegin(), 540 diag::warn_initializer_string_for_char_array_too_long, 541 strLiteral->getSourceRange()); 542 } else { 543 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 544 } 545 // Set type from "char *" to "constant array of char". 546 strLiteral->setType(DeclT); 547 // For now, we always return false (meaning success). 548 return false; 549} 550 551StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 552 const ArrayType *AT = DeclType->getAsArrayType(); 553 if (AT && AT->getElementType()->isCharType()) { 554 return dyn_cast<StringLiteral>(Init); 555 } 556 return 0; 557} 558 559// CheckInitializerListTypes - Checks the types of elements of an initializer 560// list. This function is recursive: it calls itself to initialize subelements 561// of aggregate types. Note that the topLevel parameter essentially refers to 562// whether this expression "owns" the initializer list passed in, or if this 563// initialization is taking elements out of a parent initializer. Each 564// call to this function adds zero or more to startIndex, reports any errors, 565// and returns true if it found any inconsistent types. 566bool Sema::CheckInitializerListTypes(InitListExpr*& IList, QualType &DeclType, 567 bool topLevel, unsigned& startIndex) { 568 bool hadError = false; 569 570 if (DeclType->isScalarType()) { 571 // The simplest case: initializing a single scalar 572 if (topLevel) { 573 Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init, 574 IList->getSourceRange()); 575 } 576 if (startIndex < IList->getNumInits()) { 577 Expr* expr = IList->getInit(startIndex); 578 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 579 // FIXME: Should an error be reported here instead? 580 unsigned newIndex = 0; 581 CheckInitializerListTypes(SubInitList, DeclType, true, newIndex); 582 } else { 583 hadError |= CheckInitExpr(expr, IList, startIndex, DeclType); 584 } 585 ++startIndex; 586 } 587 // FIXME: Should an error be reported for empty initializer list + scalar? 588 } else if (DeclType->isVectorType()) { 589 if (startIndex < IList->getNumInits()) { 590 const VectorType *VT = DeclType->getAsVectorType(); 591 int maxElements = VT->getNumElements(); 592 QualType elementType = VT->getElementType(); 593 594 for (int i = 0; i < maxElements; ++i) { 595 // Don't attempt to go past the end of the init list 596 if (startIndex >= IList->getNumInits()) 597 break; 598 Expr* expr = IList->getInit(startIndex); 599 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 600 unsigned newIndex = 0; 601 hadError |= CheckInitializerListTypes(SubInitList, elementType, 602 true, newIndex); 603 ++startIndex; 604 } else { 605 hadError |= CheckInitializerListTypes(IList, elementType, 606 false, startIndex); 607 } 608 } 609 } 610 } else if (DeclType->isAggregateType() || DeclType->isUnionType()) { 611 if (DeclType->isStructureType() || DeclType->isUnionType()) { 612 if (startIndex < IList->getNumInits() && !topLevel && 613 Context.typesAreCompatible(IList->getInit(startIndex)->getType(), 614 DeclType)) { 615 // We found a compatible struct; per the standard, this initializes the 616 // struct. (The C standard technically says that this only applies for 617 // initializers for declarations with automatic scope; however, this 618 // construct is unambiguous anyway because a struct cannot contain 619 // a type compatible with itself. We'll output an error when we check 620 // if the initializer is constant.) 621 // FIXME: Is a call to CheckSingleInitializer required here? 622 ++startIndex; 623 } else { 624 RecordDecl* structDecl = DeclType->getAsRecordType()->getDecl(); 625 626 // If the record is invalid, some of it's members are invalid. To avoid 627 // confusion, we forgo checking the intializer for the entire record. 628 if (structDecl->isInvalidDecl()) 629 return true; 630 631 // If structDecl is a forward declaration, this loop won't do anything; 632 // That's okay, because an error should get printed out elsewhere. It 633 // might be worthwhile to skip over the rest of the initializer, though. 634 int numMembers = structDecl->getNumMembers() - 635 structDecl->hasFlexibleArrayMember(); 636 for (int i = 0; i < numMembers; i++) { 637 // Don't attempt to go past the end of the init list 638 if (startIndex >= IList->getNumInits()) 639 break; 640 FieldDecl * curField = structDecl->getMember(i); 641 if (!curField->getIdentifier()) { 642 // Don't initialize unnamed fields, e.g. "int : 20;" 643 continue; 644 } 645 QualType fieldType = curField->getType(); 646 Expr* expr = IList->getInit(startIndex); 647 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 648 unsigned newStart = 0; 649 hadError |= CheckInitializerListTypes(SubInitList, fieldType, 650 true, newStart); 651 ++startIndex; 652 } else { 653 hadError |= CheckInitializerListTypes(IList, fieldType, 654 false, startIndex); 655 } 656 if (DeclType->isUnionType()) 657 break; 658 } 659 // FIXME: Implement flexible array initialization GCC extension (it's a 660 // really messy extension to implement, unfortunately...the necessary 661 // information isn't actually even here!) 662 } 663 } else if (DeclType->isArrayType()) { 664 // Check for the special-case of initializing an array with a string. 665 if (startIndex < IList->getNumInits()) { 666 if (StringLiteral *lit = IsStringLiteralInit(IList->getInit(startIndex), 667 DeclType)) { 668 CheckStringLiteralInit(lit, DeclType); 669 ++startIndex; 670 if (topLevel && startIndex < IList->getNumInits()) { 671 // We have leftover initializers; warn 672 Diag(IList->getInit(startIndex)->getLocStart(), 673 diag::err_excess_initializers_in_char_array_initializer, 674 IList->getInit(startIndex)->getSourceRange()); 675 } 676 return false; 677 } 678 } 679 int maxElements; 680 if (DeclType->isIncompleteArrayType()) { 681 // FIXME: use a proper constant 682 maxElements = 0x7FFFFFFF; 683 } else if (const VariableArrayType *VAT = 684 DeclType->getAsVariableArrayType()) { 685 // Check for VLAs; in standard C it would be possible to check this 686 // earlier, but I don't know where clang accepts VLAs (gcc accepts 687 // them in all sorts of strange places). 688 Diag(VAT->getSizeExpr()->getLocStart(), 689 diag::err_variable_object_no_init, 690 VAT->getSizeExpr()->getSourceRange()); 691 hadError = true; 692 maxElements = 0x7FFFFFFF; 693 } else { 694 const ConstantArrayType *CAT = DeclType->getAsConstantArrayType(); 695 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 696 } 697 QualType elementType = DeclType->getAsArrayType()->getElementType(); 698 int numElements = 0; 699 for (int i = 0; i < maxElements; ++i, ++numElements) { 700 // Don't attempt to go past the end of the init list 701 if (startIndex >= IList->getNumInits()) 702 break; 703 Expr* expr = IList->getInit(startIndex); 704 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 705 unsigned newIndex = 0; 706 hadError |= CheckInitializerListTypes(SubInitList, elementType, 707 true, newIndex); 708 ++startIndex; 709 } else { 710 hadError |= CheckInitializerListTypes(IList, elementType, 711 false, startIndex); 712 } 713 } 714 if (DeclType->isIncompleteArrayType()) { 715 // If this is an incomplete array type, the actual type needs to 716 // be calculated here 717 if (numElements == 0) { 718 // Sizing an array implicitly to zero is not allowed 719 // (It could in theory be allowed, but it doesn't really matter.) 720 Diag(IList->getLocStart(), 721 diag::err_at_least_one_initializer_needed_to_size_array); 722 hadError = true; 723 } else { 724 llvm::APSInt ConstVal(32); 725 ConstVal = numElements; 726 DeclType = Context.getConstantArrayType(elementType, ConstVal, 727 ArrayType::Normal, 0); 728 } 729 } 730 } else { 731 assert(0 && "Aggregate that isn't a function or array?!"); 732 } 733 } else { 734 // In C, all types are either scalars or aggregates, but 735 // additional handling is needed here for C++ (and possibly others?). 736 assert(0 && "Unsupported initializer type"); 737 } 738 739 // If this init list is a base list, we set the type; an initializer doesn't 740 // fundamentally have a type, but this makes the ASTs a bit easier to read 741 if (topLevel) 742 IList->setType(DeclType); 743 744 if (topLevel && startIndex < IList->getNumInits()) { 745 // We have leftover initializers; warn 746 Diag(IList->getInit(startIndex)->getLocStart(), 747 diag::warn_excess_initializers, 748 IList->getInit(startIndex)->getSourceRange()); 749 } 750 return hadError; 751} 752 753bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 754 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 755 // of unknown size ("[]") or an object type that is not a variable array type. 756 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 757 return Diag(VAT->getSizeExpr()->getLocStart(), 758 diag::err_variable_object_no_init, 759 VAT->getSizeExpr()->getSourceRange()); 760 761 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 762 if (!InitList) { 763 // FIXME: Handle wide strings 764 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 765 return CheckStringLiteralInit(strLiteral, DeclType); 766 767 if (DeclType->isArrayType()) 768 return Diag(Init->getLocStart(), 769 diag::err_array_init_list_required, 770 Init->getSourceRange()); 771 772 return CheckSingleInitializer(Init, DeclType); 773 } 774#if 0 775 unsigned newIndex = 0; 776 return CheckInitializerListTypes(InitList, DeclType, true, newIndex); 777#else 778 InitListChecker CheckInitList(this, InitList, DeclType); 779 return CheckInitList.HadError(); 780#endif 781} 782 783Sema::DeclTy * 784Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 785 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 786 IdentifierInfo *II = D.getIdentifier(); 787 788 // All of these full declarators require an identifier. If it doesn't have 789 // one, the ParsedFreeStandingDeclSpec action should be used. 790 if (II == 0) { 791 Diag(D.getDeclSpec().getSourceRange().getBegin(), 792 diag::err_declarator_need_ident, 793 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 794 return 0; 795 } 796 797 // The scope passed in may not be a decl scope. Zip up the scope tree until 798 // we find one that is. 799 while ((S->getFlags() & Scope::DeclScope) == 0) 800 S = S->getParent(); 801 802 // See if this is a redefinition of a variable in the same scope. 803 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 804 ScopedDecl *New; 805 bool InvalidDecl = false; 806 807 // In C++, the previous declaration we find might be a tag type 808 // (class or enum). In this case, the new declaration will hide the 809 // tag type. 810 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 811 PrevDecl = 0; 812 813 QualType R = GetTypeForDeclarator(D, S); 814 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 815 816 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 817 // Check that there are no default arguments (C++ only). 818 if (getLangOptions().CPlusPlus) 819 CheckExtraCXXDefaultArguments(D); 820 821 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 822 if (!NewTD) return 0; 823 824 // Handle attributes prior to checking for duplicates in MergeVarDecl 825 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 826 D.getAttributes()); 827 // Merge the decl with the existing one if appropriate. If the decl is 828 // in an outer scope, it isn't the same thing. 829 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 830 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 831 if (NewTD == 0) return 0; 832 } 833 New = NewTD; 834 if (S->getFnParent() == 0) { 835 // C99 6.7.7p2: If a typedef name specifies a variably modified type 836 // then it shall have block scope. 837 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 838 // FIXME: Diagnostic needs to be fixed. 839 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 840 InvalidDecl = true; 841 } 842 } 843 } else if (R.getTypePtr()->isFunctionType()) { 844 FunctionDecl::StorageClass SC = FunctionDecl::None; 845 switch (D.getDeclSpec().getStorageClassSpec()) { 846 default: assert(0 && "Unknown storage class!"); 847 case DeclSpec::SCS_auto: 848 case DeclSpec::SCS_register: 849 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 850 R.getAsString()); 851 InvalidDecl = true; 852 break; 853 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 854 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 855 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 856 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 857 } 858 859 bool isInline = D.getDeclSpec().isInlineSpecified(); 860 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 861 D.getIdentifierLoc(), 862 II, R, SC, isInline, 863 LastDeclarator); 864 // Handle attributes. 865 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 866 D.getAttributes()); 867 868 // Copy the parameter declarations from the declarator D to 869 // the function declaration NewFD, if they are available. 870 if (D.getNumTypeObjects() > 0 && 871 D.getTypeObject(0).Fun.hasPrototype) { 872 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 873 874 // Create Decl objects for each parameter, adding them to the 875 // FunctionDecl. 876 llvm::SmallVector<ParmVarDecl*, 16> Params; 877 878 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 879 // function that takes no arguments, not a function that takes a 880 // single void argument. 881 // We let through "const void" here because Sema::GetTypeForDeclarator 882 // already checks for that case. 883 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 884 FTI.ArgInfo[0].Param && 885 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 886 // empty arg list, don't push any params. 887 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 888 889 // In C++, the empty parameter-type-list must be spelled "void"; a 890 // typedef of void is not permitted. 891 if (getLangOptions().CPlusPlus && 892 Param->getType().getUnqualifiedType() != Context.VoidTy) { 893 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 894 } 895 896 } else { 897 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 898 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 899 } 900 901 NewFD->setParams(&Params[0], Params.size()); 902 } 903 904 // Merge the decl with the existing one if appropriate. Since C functions 905 // are in a flat namespace, make sure we consider decls in outer scopes. 906 if (PrevDecl && 907 (!getLangOptions().CPlusPlus || 908 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { 909 bool Redeclaration = false; 910 NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); 911 if (NewFD == 0) return 0; 912 if (Redeclaration) { 913 NewFD->setPreviousDeclaration(cast<FunctionDecl>(PrevDecl)); 914 } 915 } 916 New = NewFD; 917 918 // In C++, check default arguments now that we have merged decls. 919 if (getLangOptions().CPlusPlus) 920 CheckCXXDefaultArguments(NewFD); 921 } else { 922 // Check that there are no default arguments (C++ only). 923 if (getLangOptions().CPlusPlus) 924 CheckExtraCXXDefaultArguments(D); 925 926 if (R.getTypePtr()->isObjCInterfaceType()) { 927 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 928 D.getIdentifier()->getName()); 929 InvalidDecl = true; 930 } 931 932 VarDecl *NewVD; 933 VarDecl::StorageClass SC; 934 switch (D.getDeclSpec().getStorageClassSpec()) { 935 default: assert(0 && "Unknown storage class!"); 936 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 937 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 938 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 939 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 940 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 941 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 942 } 943 if (S->getFnParent() == 0) { 944 // C99 6.9p2: The storage-class specifiers auto and register shall not 945 // appear in the declaration specifiers in an external declaration. 946 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 947 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 948 R.getAsString()); 949 InvalidDecl = true; 950 } 951 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 952 II, R, SC, LastDeclarator); 953 } else { 954 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 955 II, R, SC, LastDeclarator); 956 } 957 // Handle attributes prior to checking for duplicates in MergeVarDecl 958 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 959 D.getAttributes()); 960 961 // Emit an error if an address space was applied to decl with local storage. 962 // This includes arrays of objects with address space qualifiers, but not 963 // automatic variables that point to other address spaces. 964 // ISO/IEC TR 18037 S5.1.2 965 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 966 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 967 InvalidDecl = true; 968 } 969 // Merge the decl with the existing one if appropriate. If the decl is 970 // in an outer scope, it isn't the same thing. 971 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 972 NewVD = MergeVarDecl(NewVD, PrevDecl); 973 if (NewVD == 0) return 0; 974 } 975 New = NewVD; 976 } 977 978 // If this has an identifier, add it to the scope stack. 979 if (II) 980 PushOnScopeChains(New, S); 981 // If any semantic error occurred, mark the decl as invalid. 982 if (D.getInvalidType() || InvalidDecl) 983 New->setInvalidDecl(); 984 985 return New; 986} 987 988bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 989 switch (Init->getStmtClass()) { 990 default: 991 Diag(Init->getExprLoc(), 992 diag::err_init_element_not_constant, Init->getSourceRange()); 993 return true; 994 case Expr::ParenExprClass: { 995 const ParenExpr* PE = cast<ParenExpr>(Init); 996 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 997 } 998 case Expr::CompoundLiteralExprClass: 999 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1000 case Expr::DeclRefExprClass: { 1001 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1002 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1003 if (VD->hasGlobalStorage()) 1004 return false; 1005 Diag(Init->getExprLoc(), 1006 diag::err_init_element_not_constant, Init->getSourceRange()); 1007 return true; 1008 } 1009 if (isa<FunctionDecl>(D)) 1010 return false; 1011 Diag(Init->getExprLoc(), 1012 diag::err_init_element_not_constant, Init->getSourceRange()); 1013 return true; 1014 } 1015 case Expr::MemberExprClass: { 1016 const MemberExpr *M = cast<MemberExpr>(Init); 1017 if (M->isArrow()) 1018 return CheckAddressConstantExpression(M->getBase()); 1019 return CheckAddressConstantExpressionLValue(M->getBase()); 1020 } 1021 case Expr::ArraySubscriptExprClass: { 1022 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1023 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1024 return CheckAddressConstantExpression(ASE->getBase()) || 1025 CheckArithmeticConstantExpression(ASE->getIdx()); 1026 } 1027 case Expr::StringLiteralClass: 1028 case Expr::PreDefinedExprClass: 1029 return false; 1030 case Expr::UnaryOperatorClass: { 1031 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1032 1033 // C99 6.6p9 1034 if (Exp->getOpcode() == UnaryOperator::Deref) 1035 return CheckAddressConstantExpression(Exp->getSubExpr()); 1036 1037 Diag(Init->getExprLoc(), 1038 diag::err_init_element_not_constant, Init->getSourceRange()); 1039 return true; 1040 } 1041 } 1042} 1043 1044bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1045 switch (Init->getStmtClass()) { 1046 default: 1047 Diag(Init->getExprLoc(), 1048 diag::err_init_element_not_constant, Init->getSourceRange()); 1049 return true; 1050 case Expr::ParenExprClass: { 1051 const ParenExpr* PE = cast<ParenExpr>(Init); 1052 return CheckAddressConstantExpression(PE->getSubExpr()); 1053 } 1054 case Expr::StringLiteralClass: 1055 case Expr::ObjCStringLiteralClass: 1056 return false; 1057 case Expr::CallExprClass: { 1058 const CallExpr *CE = cast<CallExpr>(Init); 1059 if (CE->isBuiltinConstantExpr()) 1060 return false; 1061 Diag(Init->getExprLoc(), 1062 diag::err_init_element_not_constant, Init->getSourceRange()); 1063 return true; 1064 } 1065 case Expr::UnaryOperatorClass: { 1066 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1067 1068 // C99 6.6p9 1069 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1070 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1071 1072 if (Exp->getOpcode() == UnaryOperator::Extension) 1073 return CheckAddressConstantExpression(Exp->getSubExpr()); 1074 1075 Diag(Init->getExprLoc(), 1076 diag::err_init_element_not_constant, Init->getSourceRange()); 1077 return true; 1078 } 1079 case Expr::BinaryOperatorClass: { 1080 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1081 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1082 1083 Expr *PExp = Exp->getLHS(); 1084 Expr *IExp = Exp->getRHS(); 1085 if (IExp->getType()->isPointerType()) 1086 std::swap(PExp, IExp); 1087 1088 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1089 return CheckAddressConstantExpression(PExp) || 1090 CheckArithmeticConstantExpression(IExp); 1091 } 1092 case Expr::ImplicitCastExprClass: { 1093 const Expr* SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1094 1095 // Check for implicit promotion 1096 if (SubExpr->getType()->isFunctionType() || 1097 SubExpr->getType()->isArrayType()) 1098 return CheckAddressConstantExpressionLValue(SubExpr); 1099 1100 // Check for pointer->pointer cast 1101 if (SubExpr->getType()->isPointerType()) 1102 return CheckAddressConstantExpression(SubExpr); 1103 1104 if (SubExpr->getType()->isArithmeticType()) 1105 return CheckArithmeticConstantExpression(SubExpr); 1106 1107 Diag(Init->getExprLoc(), 1108 diag::err_init_element_not_constant, Init->getSourceRange()); 1109 return true; 1110 } 1111 case Expr::CastExprClass: { 1112 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1113 1114 // Check for pointer->pointer cast 1115 if (SubExpr->getType()->isPointerType()) 1116 return CheckAddressConstantExpression(SubExpr); 1117 1118 // FIXME: Should we pedwarn for (int*)(0+0)? 1119 if (SubExpr->getType()->isArithmeticType()) 1120 return CheckArithmeticConstantExpression(SubExpr); 1121 1122 Diag(Init->getExprLoc(), 1123 diag::err_init_element_not_constant, Init->getSourceRange()); 1124 return true; 1125 } 1126 case Expr::ConditionalOperatorClass: { 1127 // FIXME: Should we pedwarn here? 1128 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1129 if (!Exp->getCond()->getType()->isArithmeticType()) { 1130 Diag(Init->getExprLoc(), 1131 diag::err_init_element_not_constant, Init->getSourceRange()); 1132 return true; 1133 } 1134 if (CheckArithmeticConstantExpression(Exp->getCond())) 1135 return true; 1136 if (Exp->getLHS() && 1137 CheckAddressConstantExpression(Exp->getLHS())) 1138 return true; 1139 return CheckAddressConstantExpression(Exp->getRHS()); 1140 } 1141 case Expr::AddrLabelExprClass: 1142 return false; 1143 } 1144} 1145 1146bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1147 switch (Init->getStmtClass()) { 1148 default: 1149 Diag(Init->getExprLoc(), 1150 diag::err_init_element_not_constant, Init->getSourceRange()); 1151 return true; 1152 case Expr::ParenExprClass: { 1153 const ParenExpr* PE = cast<ParenExpr>(Init); 1154 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1155 } 1156 case Expr::FloatingLiteralClass: 1157 case Expr::IntegerLiteralClass: 1158 case Expr::CharacterLiteralClass: 1159 case Expr::ImaginaryLiteralClass: 1160 case Expr::TypesCompatibleExprClass: 1161 case Expr::CXXBoolLiteralExprClass: 1162 return false; 1163 case Expr::CallExprClass: { 1164 const CallExpr *CE = cast<CallExpr>(Init); 1165 if (CE->isBuiltinConstantExpr()) 1166 return false; 1167 Diag(Init->getExprLoc(), 1168 diag::err_init_element_not_constant, Init->getSourceRange()); 1169 return true; 1170 } 1171 case Expr::DeclRefExprClass: { 1172 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1173 if (isa<EnumConstantDecl>(D)) 1174 return false; 1175 Diag(Init->getExprLoc(), 1176 diag::err_init_element_not_constant, Init->getSourceRange()); 1177 return true; 1178 } 1179 case Expr::CompoundLiteralExprClass: 1180 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1181 // but vectors are allowed to be magic. 1182 if (Init->getType()->isVectorType()) 1183 return false; 1184 Diag(Init->getExprLoc(), 1185 diag::err_init_element_not_constant, Init->getSourceRange()); 1186 return true; 1187 case Expr::UnaryOperatorClass: { 1188 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1189 1190 switch (Exp->getOpcode()) { 1191 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1192 // See C99 6.6p3. 1193 default: 1194 Diag(Init->getExprLoc(), 1195 diag::err_init_element_not_constant, Init->getSourceRange()); 1196 return true; 1197 case UnaryOperator::SizeOf: 1198 case UnaryOperator::AlignOf: 1199 case UnaryOperator::OffsetOf: 1200 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1201 // See C99 6.5.3.4p2 and 6.6p3. 1202 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1203 return false; 1204 Diag(Init->getExprLoc(), 1205 diag::err_init_element_not_constant, Init->getSourceRange()); 1206 return true; 1207 case UnaryOperator::Extension: 1208 case UnaryOperator::LNot: 1209 case UnaryOperator::Plus: 1210 case UnaryOperator::Minus: 1211 case UnaryOperator::Not: 1212 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1213 } 1214 } 1215 case Expr::SizeOfAlignOfTypeExprClass: { 1216 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1217 // Special check for void types, which are allowed as an extension 1218 if (Exp->getArgumentType()->isVoidType()) 1219 return false; 1220 // alignof always evaluates to a constant. 1221 // FIXME: is sizeof(int[3.0]) a constant expression? 1222 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1223 Diag(Init->getExprLoc(), 1224 diag::err_init_element_not_constant, Init->getSourceRange()); 1225 return true; 1226 } 1227 return false; 1228 } 1229 case Expr::BinaryOperatorClass: { 1230 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1231 1232 if (Exp->getLHS()->getType()->isArithmeticType() && 1233 Exp->getRHS()->getType()->isArithmeticType()) { 1234 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1235 CheckArithmeticConstantExpression(Exp->getRHS()); 1236 } 1237 1238 Diag(Init->getExprLoc(), 1239 diag::err_init_element_not_constant, Init->getSourceRange()); 1240 return true; 1241 } 1242 case Expr::ImplicitCastExprClass: 1243 case Expr::CastExprClass: { 1244 const Expr *SubExpr; 1245 if (const CastExpr *C = dyn_cast<CastExpr>(Init)) { 1246 SubExpr = C->getSubExpr(); 1247 } else { 1248 SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1249 } 1250 1251 if (SubExpr->getType()->isArithmeticType()) 1252 return CheckArithmeticConstantExpression(SubExpr); 1253 1254 Diag(Init->getExprLoc(), 1255 diag::err_init_element_not_constant, Init->getSourceRange()); 1256 return true; 1257 } 1258 case Expr::ConditionalOperatorClass: { 1259 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1260 if (CheckArithmeticConstantExpression(Exp->getCond())) 1261 return true; 1262 if (Exp->getLHS() && 1263 CheckArithmeticConstantExpression(Exp->getLHS())) 1264 return true; 1265 return CheckArithmeticConstantExpression(Exp->getRHS()); 1266 } 1267 } 1268} 1269 1270bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1271 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1272 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1273 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1274 1275 if (Init->getType()->isReferenceType()) { 1276 // FIXME: Work out how the heck reference types work 1277 return false; 1278#if 0 1279 // A reference is constant if the address of the expression 1280 // is constant 1281 // We look through initlists here to simplify 1282 // CheckAddressConstantExpressionLValue. 1283 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1284 assert(Exp->getNumInits() > 0 && 1285 "Refernce initializer cannot be empty"); 1286 Init = Exp->getInit(0); 1287 } 1288 return CheckAddressConstantExpressionLValue(Init); 1289#endif 1290 } 1291 1292 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1293 unsigned numInits = Exp->getNumInits(); 1294 for (unsigned i = 0; i < numInits; i++) { 1295 // FIXME: Need to get the type of the declaration for C++, 1296 // because it could be a reference? 1297 if (CheckForConstantInitializer(Exp->getInit(i), 1298 Exp->getInit(i)->getType())) 1299 return true; 1300 } 1301 return false; 1302 } 1303 1304 if (Init->isNullPointerConstant(Context)) 1305 return false; 1306 if (Init->getType()->isArithmeticType()) { 1307 QualType InitTy = Init->getType().getCanonicalType().getUnqualifiedType(); 1308 if (InitTy == Context.BoolTy) { 1309 // Special handling for pointers implicitly cast to bool; 1310 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1311 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1312 Expr* SubE = ICE->getSubExpr(); 1313 if (SubE->getType()->isPointerType() || 1314 SubE->getType()->isArrayType() || 1315 SubE->getType()->isFunctionType()) { 1316 return CheckAddressConstantExpression(Init); 1317 } 1318 } 1319 } else if (InitTy->isIntegralType()) { 1320 Expr* SubE = 0; 1321 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) 1322 SubE = ICE->getSubExpr(); 1323 else if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1324 SubE = CE->getSubExpr(); 1325 // Special check for pointer cast to int; we allow as an extension 1326 // an address constant cast to an integer if the integer 1327 // is of an appropriate width (this sort of code is apparently used 1328 // in some places). 1329 // FIXME: Add pedwarn? 1330 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1331 if (SubE && (SubE->getType()->isPointerType() || 1332 SubE->getType()->isArrayType() || 1333 SubE->getType()->isFunctionType())) { 1334 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1335 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1336 if (IntWidth >= PointerWidth) 1337 return CheckAddressConstantExpression(Init); 1338 } 1339 } 1340 1341 return CheckArithmeticConstantExpression(Init); 1342 } 1343 1344 if (Init->getType()->isPointerType()) 1345 return CheckAddressConstantExpression(Init); 1346 1347 // An array type at the top level that isn't an init-list must 1348 // be a string literal 1349 if (Init->getType()->isArrayType()) 1350 return false; 1351 1352 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1353 Init->getSourceRange()); 1354 return true; 1355} 1356 1357void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1358 Decl *RealDecl = static_cast<Decl *>(dcl); 1359 Expr *Init = static_cast<Expr *>(init); 1360 assert(Init && "missing initializer"); 1361 1362 // If there is no declaration, there was an error parsing it. Just ignore 1363 // the initializer. 1364 if (RealDecl == 0) { 1365 delete Init; 1366 return; 1367 } 1368 1369 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1370 if (!VDecl) { 1371 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1372 diag::err_illegal_initializer); 1373 RealDecl->setInvalidDecl(); 1374 return; 1375 } 1376 // Get the decls type and save a reference for later, since 1377 // CheckInitializerTypes may change it. 1378 QualType DclT = VDecl->getType(), SavT = DclT; 1379 if (VDecl->isBlockVarDecl()) { 1380 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1381 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1382 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1383 VDecl->setInvalidDecl(); 1384 } else if (!VDecl->isInvalidDecl()) { 1385 if (CheckInitializerTypes(Init, DclT)) 1386 VDecl->setInvalidDecl(); 1387 if (SC == VarDecl::Static) // C99 6.7.8p4. 1388 CheckForConstantInitializer(Init, DclT); 1389 } 1390 } else if (VDecl->isFileVarDecl()) { 1391 if (VDecl->getStorageClass() == VarDecl::Extern) 1392 Diag(VDecl->getLocation(), diag::warn_extern_init); 1393 if (!VDecl->isInvalidDecl()) 1394 if (CheckInitializerTypes(Init, DclT)) 1395 VDecl->setInvalidDecl(); 1396 1397 // C99 6.7.8p4. All file scoped initializers need to be constant. 1398 CheckForConstantInitializer(Init, DclT); 1399 } 1400 // If the type changed, it means we had an incomplete type that was 1401 // completed by the initializer. For example: 1402 // int ary[] = { 1, 3, 5 }; 1403 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1404 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1405 VDecl->setType(DclT); 1406 Init->setType(DclT); 1407 } 1408 1409 // Attach the initializer to the decl. 1410 VDecl->setInit(Init); 1411 return; 1412} 1413 1414/// The declarators are chained together backwards, reverse the list. 1415Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1416 // Often we have single declarators, handle them quickly. 1417 Decl *GroupDecl = static_cast<Decl*>(group); 1418 if (GroupDecl == 0) 1419 return 0; 1420 1421 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1422 ScopedDecl *NewGroup = 0; 1423 if (Group->getNextDeclarator() == 0) 1424 NewGroup = Group; 1425 else { // reverse the list. 1426 while (Group) { 1427 ScopedDecl *Next = Group->getNextDeclarator(); 1428 Group->setNextDeclarator(NewGroup); 1429 NewGroup = Group; 1430 Group = Next; 1431 } 1432 } 1433 // Perform semantic analysis that depends on having fully processed both 1434 // the declarator and initializer. 1435 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1436 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1437 if (!IDecl) 1438 continue; 1439 QualType T = IDecl->getType(); 1440 1441 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1442 // static storage duration, it shall not have a variable length array. 1443 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1444 IDecl->getStorageClass() == VarDecl::Static) { 1445 if (T->getAsVariableArrayType()) { 1446 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1447 IDecl->setInvalidDecl(); 1448 } 1449 } 1450 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1451 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1452 if (IDecl->isBlockVarDecl() && 1453 IDecl->getStorageClass() != VarDecl::Extern) { 1454 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1455 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1456 T.getAsString()); 1457 IDecl->setInvalidDecl(); 1458 } 1459 } 1460 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1461 // object that has file scope without an initializer, and without a 1462 // storage-class specifier or with the storage-class specifier "static", 1463 // constitutes a tentative definition. Note: A tentative definition with 1464 // external linkage is valid (C99 6.2.2p5). 1465 if (IDecl && !IDecl->getInit() && 1466 (IDecl->getStorageClass() == VarDecl::Static || 1467 IDecl->getStorageClass() == VarDecl::None)) { 1468 if (T->isIncompleteArrayType()) { 1469 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1470 // array to be completed. Don't issue a diagnostic. 1471 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1472 // C99 6.9.2p3: If the declaration of an identifier for an object is 1473 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1474 // declared type shall not be an incomplete type. 1475 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1476 T.getAsString()); 1477 IDecl->setInvalidDecl(); 1478 } 1479 } 1480 } 1481 return NewGroup; 1482} 1483 1484/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1485/// to introduce parameters into function prototype scope. 1486Sema::DeclTy * 1487Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1488 DeclSpec &DS = D.getDeclSpec(); 1489 1490 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1491 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1492 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1493 Diag(DS.getStorageClassSpecLoc(), 1494 diag::err_invalid_storage_class_in_func_decl); 1495 DS.ClearStorageClassSpecs(); 1496 } 1497 if (DS.isThreadSpecified()) { 1498 Diag(DS.getThreadSpecLoc(), 1499 diag::err_invalid_storage_class_in_func_decl); 1500 DS.ClearStorageClassSpecs(); 1501 } 1502 1503 // Check that there are no default arguments inside the type of this 1504 // parameter (C++ only). 1505 if (getLangOptions().CPlusPlus) 1506 CheckExtraCXXDefaultArguments(D); 1507 1508 // In this context, we *do not* check D.getInvalidType(). If the declarator 1509 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1510 // though it will not reflect the user specified type. 1511 QualType parmDeclType = GetTypeForDeclarator(D, S); 1512 1513 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1514 1515 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1516 // Can this happen for params? We already checked that they don't conflict 1517 // among each other. Here they can only shadow globals, which is ok. 1518 IdentifierInfo *II = D.getIdentifier(); 1519 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1520 if (S->isDeclScope(PrevDecl)) { 1521 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1522 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1523 1524 // Recover by removing the name 1525 II = 0; 1526 D.SetIdentifier(0, D.getIdentifierLoc()); 1527 } 1528 } 1529 1530 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1531 // Doing the promotion here has a win and a loss. The win is the type for 1532 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1533 // code generator). The loss is the orginal type isn't preserved. For example: 1534 // 1535 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1536 // int blockvardecl[5]; 1537 // sizeof(parmvardecl); // size == 4 1538 // sizeof(blockvardecl); // size == 20 1539 // } 1540 // 1541 // For expressions, all implicit conversions are captured using the 1542 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1543 // 1544 // FIXME: If a source translation tool needs to see the original type, then 1545 // we need to consider storing both types (in ParmVarDecl)... 1546 // 1547 if (parmDeclType->isArrayType()) { 1548 // int x[restrict 4] -> int *restrict 1549 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1550 } else if (parmDeclType->isFunctionType()) 1551 parmDeclType = Context.getPointerType(parmDeclType); 1552 1553 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1554 D.getIdentifierLoc(), II, 1555 parmDeclType, VarDecl::None, 1556 0, 0); 1557 1558 if (D.getInvalidType()) 1559 New->setInvalidDecl(); 1560 1561 if (II) 1562 PushOnScopeChains(New, S); 1563 1564 HandleDeclAttributes(New, D.getDeclSpec().getAttributes(), 1565 D.getAttributes()); 1566 return New; 1567 1568} 1569 1570Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1571 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1572 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1573 "Not a function declarator!"); 1574 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1575 1576 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1577 // for a K&R function. 1578 if (!FTI.hasPrototype) { 1579 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1580 if (FTI.ArgInfo[i].Param == 0) { 1581 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1582 FTI.ArgInfo[i].Ident->getName()); 1583 // Implicitly declare the argument as type 'int' for lack of a better 1584 // type. 1585 DeclSpec DS; 1586 const char* PrevSpec; // unused 1587 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1588 PrevSpec); 1589 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1590 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1591 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1592 } 1593 } 1594 1595 // Since this is a function definition, act as though we have information 1596 // about the arguments. 1597 if (FTI.NumArgs) 1598 FTI.hasPrototype = true; 1599 } else { 1600 // FIXME: Diagnose arguments without names in C. 1601 } 1602 1603 Scope *GlobalScope = FnBodyScope->getParent(); 1604 1605 // See if this is a redefinition. 1606 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1607 GlobalScope); 1608 if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { 1609 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1610 const FunctionDecl *Definition; 1611 if (FD->getBody(Definition)) { 1612 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1613 D.getIdentifier()->getName()); 1614 Diag(Definition->getLocation(), diag::err_previous_definition); 1615 } 1616 } 1617 } 1618 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1619 FunctionDecl *FD = cast<FunctionDecl>(decl); 1620 CurFunctionDecl = FD; 1621 PushDeclContext(FD); 1622 1623 // Check the validity of our function parameters 1624 CheckParmsForFunctionDef(FD); 1625 1626 // Introduce our parameters into the function scope 1627 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1628 ParmVarDecl *Param = FD->getParamDecl(p); 1629 // If this has an identifier, add it to the scope stack. 1630 if (Param->getIdentifier()) 1631 PushOnScopeChains(Param, FnBodyScope); 1632 } 1633 1634 return FD; 1635} 1636 1637Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1638 Decl *dcl = static_cast<Decl *>(D); 1639 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1640 FD->setBody((Stmt*)Body); 1641 assert(FD == CurFunctionDecl && "Function parsing confused"); 1642 CurFunctionDecl = 0; 1643 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1644 MD->setBody((Stmt*)Body); 1645 CurMethodDecl = 0; 1646 } 1647 PopDeclContext(); 1648 // Verify and clean out per-function state. 1649 1650 // Check goto/label use. 1651 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1652 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1653 // Verify that we have no forward references left. If so, there was a goto 1654 // or address of a label taken, but no definition of it. Label fwd 1655 // definitions are indicated with a null substmt. 1656 if (I->second->getSubStmt() == 0) { 1657 LabelStmt *L = I->second; 1658 // Emit error. 1659 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1660 1661 // At this point, we have gotos that use the bogus label. Stitch it into 1662 // the function body so that they aren't leaked and that the AST is well 1663 // formed. 1664 if (Body) { 1665 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1666 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1667 } else { 1668 // The whole function wasn't parsed correctly, just delete this. 1669 delete L; 1670 } 1671 } 1672 } 1673 LabelMap.clear(); 1674 1675 return D; 1676} 1677 1678/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1679/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1680ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1681 IdentifierInfo &II, Scope *S) { 1682 // Extension in C99. Legal in C90, but warn about it. 1683 if (getLangOptions().C99) 1684 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1685 else 1686 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1687 1688 // FIXME: handle stuff like: 1689 // void foo() { extern float X(); } 1690 // void bar() { X(); } <-- implicit decl for X in another scope. 1691 1692 // Set a Declarator for the implicit definition: int foo(); 1693 const char *Dummy; 1694 DeclSpec DS; 1695 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1696 Error = Error; // Silence warning. 1697 assert(!Error && "Error setting up implicit decl!"); 1698 Declarator D(DS, Declarator::BlockContext); 1699 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1700 D.SetIdentifier(&II, Loc); 1701 1702 // Insert this function into translation-unit scope. 1703 1704 DeclContext *PrevDC = CurContext; 1705 CurContext = Context.getTranslationUnitDecl(); 1706 1707 FunctionDecl *FD = 1708 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1709 FD->setImplicit(); 1710 1711 CurContext = PrevDC; 1712 1713 return FD; 1714} 1715 1716 1717TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1718 ScopedDecl *LastDeclarator) { 1719 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1720 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1721 1722 // Scope manipulation handled by caller. 1723 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1724 D.getIdentifierLoc(), 1725 D.getIdentifier(), 1726 T, LastDeclarator); 1727 if (D.getInvalidType()) 1728 NewTD->setInvalidDecl(); 1729 return NewTD; 1730} 1731 1732/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1733/// former case, Name will be non-null. In the later case, Name will be null. 1734/// TagType indicates what kind of tag this is. TK indicates whether this is a 1735/// reference/declaration/definition of a tag. 1736Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1737 SourceLocation KWLoc, IdentifierInfo *Name, 1738 SourceLocation NameLoc, AttributeList *Attr) { 1739 // If this is a use of an existing tag, it must have a name. 1740 assert((Name != 0 || TK == TK_Definition) && 1741 "Nameless record must be a definition!"); 1742 1743 Decl::Kind Kind; 1744 switch (TagType) { 1745 default: assert(0 && "Unknown tag type!"); 1746 case DeclSpec::TST_struct: Kind = Decl::Struct; break; 1747 case DeclSpec::TST_union: Kind = Decl::Union; break; 1748 case DeclSpec::TST_class: Kind = Decl::Class; break; 1749 case DeclSpec::TST_enum: Kind = Decl::Enum; break; 1750 } 1751 1752 // If this is a named struct, check to see if there was a previous forward 1753 // declaration or definition. 1754 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1755 if (ScopedDecl *PrevDecl = 1756 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1757 1758 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1759 "unexpected Decl type"); 1760 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1761 // If this is a use of a previous tag, or if the tag is already declared in 1762 // the same scope (so that the definition/declaration completes or 1763 // rementions the tag), reuse the decl. 1764 if (TK == TK_Reference || 1765 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1766 // Make sure that this wasn't declared as an enum and now used as a struct 1767 // or something similar. 1768 if (PrevDecl->getKind() != Kind) { 1769 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1770 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1771 } 1772 1773 // If this is a use or a forward declaration, we're good. 1774 if (TK != TK_Definition) 1775 return PrevDecl; 1776 1777 // Diagnose attempts to redefine a tag. 1778 if (PrevTagDecl->isDefinition()) { 1779 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1780 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1781 // If this is a redefinition, recover by making this struct be 1782 // anonymous, which will make any later references get the previous 1783 // definition. 1784 Name = 0; 1785 } else { 1786 // Okay, this is definition of a previously declared or referenced tag. 1787 // Move the location of the decl to be the definition site. 1788 PrevDecl->setLocation(NameLoc); 1789 return PrevDecl; 1790 } 1791 } 1792 // If we get here, this is a definition of a new struct type in a nested 1793 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1794 // type. 1795 } else { 1796 // The tag name clashes with a namespace name, issue an error and recover 1797 // by making this tag be anonymous. 1798 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1799 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1800 Name = 0; 1801 } 1802 } 1803 1804 // If there is an identifier, use the location of the identifier as the 1805 // location of the decl, otherwise use the location of the struct/union 1806 // keyword. 1807 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1808 1809 // Otherwise, if this is the first time we've seen this tag, create the decl. 1810 TagDecl *New; 1811 switch (Kind) { 1812 default: assert(0 && "Unknown tag kind!"); 1813 case Decl::Enum: 1814 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1815 // enum X { A, B, C } D; D should chain to X. 1816 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1817 // If this is an undefined enum, warn. 1818 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1819 break; 1820 case Decl::Union: 1821 case Decl::Struct: 1822 case Decl::Class: 1823 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1824 // struct X { int A; } D; D should chain to X. 1825 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1826 break; 1827 } 1828 1829 // If this has an identifier, add it to the scope stack. 1830 if (Name) { 1831 // The scope passed in may not be a decl scope. Zip up the scope tree until 1832 // we find one that is. 1833 while ((S->getFlags() & Scope::DeclScope) == 0) 1834 S = S->getParent(); 1835 1836 // Add it to the decl chain. 1837 PushOnScopeChains(New, S); 1838 } 1839 1840 HandleDeclAttributes(New, Attr, 0); 1841 return New; 1842} 1843 1844/// ActOnField - Each field of a struct/union/class is passed into this in order 1845/// to create a FieldDecl object for it. 1846Sema::DeclTy *Sema::ActOnField(Scope *S, 1847 SourceLocation DeclStart, 1848 Declarator &D, ExprTy *BitfieldWidth) { 1849 IdentifierInfo *II = D.getIdentifier(); 1850 Expr *BitWidth = (Expr*)BitfieldWidth; 1851 SourceLocation Loc = DeclStart; 1852 if (II) Loc = D.getIdentifierLoc(); 1853 1854 // FIXME: Unnamed fields can be handled in various different ways, for 1855 // example, unnamed unions inject all members into the struct namespace! 1856 1857 1858 if (BitWidth) { 1859 // TODO: Validate. 1860 //printf("WARNING: BITFIELDS IGNORED!\n"); 1861 1862 // 6.7.2.1p3 1863 // 6.7.2.1p4 1864 1865 } else { 1866 // Not a bitfield. 1867 1868 // validate II. 1869 1870 } 1871 1872 QualType T = GetTypeForDeclarator(D, S); 1873 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1874 bool InvalidDecl = false; 1875 1876 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1877 // than a variably modified type. 1878 if (T->isVariablyModifiedType()) { 1879 // FIXME: This diagnostic needs work 1880 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1881 InvalidDecl = true; 1882 } 1883 // FIXME: Chain fielddecls together. 1884 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1885 1886 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1887 D.getAttributes()); 1888 1889 if (D.getInvalidType() || InvalidDecl) 1890 NewFD->setInvalidDecl(); 1891 return NewFD; 1892} 1893 1894/// TranslateIvarVisibility - Translate visibility from a token ID to an 1895/// AST enum value. 1896static ObjCIvarDecl::AccessControl 1897TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1898 switch (ivarVisibility) { 1899 case tok::objc_private: return ObjCIvarDecl::Private; 1900 case tok::objc_public: return ObjCIvarDecl::Public; 1901 case tok::objc_protected: return ObjCIvarDecl::Protected; 1902 case tok::objc_package: return ObjCIvarDecl::Package; 1903 default: assert(false && "Unknown visitibility kind"); 1904 } 1905} 1906 1907/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1908/// in order to create an IvarDecl object for it. 1909Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1910 SourceLocation DeclStart, 1911 Declarator &D, ExprTy *BitfieldWidth, 1912 tok::ObjCKeywordKind Visibility) { 1913 IdentifierInfo *II = D.getIdentifier(); 1914 Expr *BitWidth = (Expr*)BitfieldWidth; 1915 SourceLocation Loc = DeclStart; 1916 if (II) Loc = D.getIdentifierLoc(); 1917 1918 // FIXME: Unnamed fields can be handled in various different ways, for 1919 // example, unnamed unions inject all members into the struct namespace! 1920 1921 1922 if (BitWidth) { 1923 // TODO: Validate. 1924 //printf("WARNING: BITFIELDS IGNORED!\n"); 1925 1926 // 6.7.2.1p3 1927 // 6.7.2.1p4 1928 1929 } else { 1930 // Not a bitfield. 1931 1932 // validate II. 1933 1934 } 1935 1936 QualType T = GetTypeForDeclarator(D, S); 1937 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1938 bool InvalidDecl = false; 1939 1940 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1941 // than a variably modified type. 1942 if (T->isVariablyModifiedType()) { 1943 // FIXME: This diagnostic needs work 1944 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1945 InvalidDecl = true; 1946 } 1947 1948 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1949 1950 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1951 D.getAttributes()); 1952 1953 if (D.getInvalidType() || InvalidDecl) 1954 NewID->setInvalidDecl(); 1955 // If we have visibility info, make sure the AST is set accordingly. 1956 if (Visibility != tok::objc_not_keyword) 1957 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1958 return NewID; 1959} 1960 1961void Sema::ActOnFields(Scope* S, 1962 SourceLocation RecLoc, DeclTy *RecDecl, 1963 DeclTy **Fields, unsigned NumFields, 1964 SourceLocation LBrac, SourceLocation RBrac) { 1965 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1966 assert(EnclosingDecl && "missing record or interface decl"); 1967 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1968 1969 if (Record && Record->isDefinition()) { 1970 // Diagnose code like: 1971 // struct S { struct S {} X; }; 1972 // We discover this when we complete the outer S. Reject and ignore the 1973 // outer S. 1974 Diag(Record->getLocation(), diag::err_nested_redefinition, 1975 Record->getKindName()); 1976 Diag(RecLoc, diag::err_previous_definition); 1977 Record->setInvalidDecl(); 1978 return; 1979 } 1980 // Verify that all the fields are okay. 1981 unsigned NumNamedMembers = 0; 1982 llvm::SmallVector<FieldDecl*, 32> RecFields; 1983 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1984 1985 for (unsigned i = 0; i != NumFields; ++i) { 1986 1987 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1988 assert(FD && "missing field decl"); 1989 1990 // Remember all fields. 1991 RecFields.push_back(FD); 1992 1993 // Get the type for the field. 1994 Type *FDTy = FD->getType().getTypePtr(); 1995 1996 // C99 6.7.2.1p2 - A field may not be a function type. 1997 if (FDTy->isFunctionType()) { 1998 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1999 FD->getName()); 2000 FD->setInvalidDecl(); 2001 EnclosingDecl->setInvalidDecl(); 2002 continue; 2003 } 2004 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 2005 if (FDTy->isIncompleteType()) { 2006 if (!Record) { // Incomplete ivar type is always an error. 2007 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2008 FD->setInvalidDecl(); 2009 EnclosingDecl->setInvalidDecl(); 2010 continue; 2011 } 2012 if (i != NumFields-1 || // ... that the last member ... 2013 Record->getKind() != Decl::Struct || // ... of a structure ... 2014 !FDTy->isArrayType()) { //... may have incomplete array type. 2015 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2016 FD->setInvalidDecl(); 2017 EnclosingDecl->setInvalidDecl(); 2018 continue; 2019 } 2020 if (NumNamedMembers < 1) { //... must have more than named member ... 2021 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 2022 FD->getName()); 2023 FD->setInvalidDecl(); 2024 EnclosingDecl->setInvalidDecl(); 2025 continue; 2026 } 2027 // Okay, we have a legal flexible array member at the end of the struct. 2028 if (Record) 2029 Record->setHasFlexibleArrayMember(true); 2030 } 2031 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 2032 /// field of another structure or the element of an array. 2033 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 2034 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 2035 // If this is a member of a union, then entire union becomes "flexible". 2036 if (Record && Record->getKind() == Decl::Union) { 2037 Record->setHasFlexibleArrayMember(true); 2038 } else { 2039 // If this is a struct/class and this is not the last element, reject 2040 // it. Note that GCC supports variable sized arrays in the middle of 2041 // structures. 2042 if (i != NumFields-1) { 2043 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 2044 FD->getName()); 2045 FD->setInvalidDecl(); 2046 EnclosingDecl->setInvalidDecl(); 2047 continue; 2048 } 2049 // We support flexible arrays at the end of structs in other structs 2050 // as an extension. 2051 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 2052 FD->getName()); 2053 if (Record) 2054 Record->setHasFlexibleArrayMember(true); 2055 } 2056 } 2057 } 2058 /// A field cannot be an Objective-c object 2059 if (FDTy->isObjCInterfaceType()) { 2060 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2061 FD->getName()); 2062 FD->setInvalidDecl(); 2063 EnclosingDecl->setInvalidDecl(); 2064 continue; 2065 } 2066 // Keep track of the number of named members. 2067 if (IdentifierInfo *II = FD->getIdentifier()) { 2068 // Detect duplicate member names. 2069 if (!FieldIDs.insert(II)) { 2070 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2071 // Find the previous decl. 2072 SourceLocation PrevLoc; 2073 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 2074 assert(i != e && "Didn't find previous def!"); 2075 if (RecFields[i]->getIdentifier() == II) { 2076 PrevLoc = RecFields[i]->getLocation(); 2077 break; 2078 } 2079 } 2080 Diag(PrevLoc, diag::err_previous_definition); 2081 FD->setInvalidDecl(); 2082 EnclosingDecl->setInvalidDecl(); 2083 continue; 2084 } 2085 ++NumNamedMembers; 2086 } 2087 } 2088 2089 // Okay, we successfully defined 'Record'. 2090 if (Record) { 2091 Record->defineBody(&RecFields[0], RecFields.size()); 2092 Consumer.HandleTagDeclDefinition(Record); 2093 } else { 2094 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2095 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2096 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2097 else if (ObjCImplementationDecl *IMPDecl = 2098 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2099 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2100 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2101 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2102 } 2103 } 2104} 2105 2106Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2107 DeclTy *lastEnumConst, 2108 SourceLocation IdLoc, IdentifierInfo *Id, 2109 SourceLocation EqualLoc, ExprTy *val) { 2110 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2111 EnumConstantDecl *LastEnumConst = 2112 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2113 Expr *Val = static_cast<Expr*>(val); 2114 2115 // The scope passed in may not be a decl scope. Zip up the scope tree until 2116 // we find one that is. 2117 while ((S->getFlags() & Scope::DeclScope) == 0) 2118 S = S->getParent(); 2119 2120 // Verify that there isn't already something declared with this name in this 2121 // scope. 2122 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2123 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 2124 if (isa<EnumConstantDecl>(PrevDecl)) 2125 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2126 else 2127 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2128 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2129 delete Val; 2130 return 0; 2131 } 2132 } 2133 2134 llvm::APSInt EnumVal(32); 2135 QualType EltTy; 2136 if (Val) { 2137 // Make sure to promote the operand type to int. 2138 UsualUnaryConversions(Val); 2139 2140 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2141 SourceLocation ExpLoc; 2142 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2143 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2144 Id->getName()); 2145 delete Val; 2146 Val = 0; // Just forget about it. 2147 } else { 2148 EltTy = Val->getType(); 2149 } 2150 } 2151 2152 if (!Val) { 2153 if (LastEnumConst) { 2154 // Assign the last value + 1. 2155 EnumVal = LastEnumConst->getInitVal(); 2156 ++EnumVal; 2157 2158 // Check for overflow on increment. 2159 if (EnumVal < LastEnumConst->getInitVal()) 2160 Diag(IdLoc, diag::warn_enum_value_overflow); 2161 2162 EltTy = LastEnumConst->getType(); 2163 } else { 2164 // First value, set to zero. 2165 EltTy = Context.IntTy; 2166 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2167 } 2168 } 2169 2170 EnumConstantDecl *New = 2171 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2172 Val, EnumVal, 2173 LastEnumConst); 2174 2175 // Register this decl in the current scope stack. 2176 PushOnScopeChains(New, S); 2177 return New; 2178} 2179 2180void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2181 DeclTy **Elements, unsigned NumElements) { 2182 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2183 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 2184 2185 // TODO: If the result value doesn't fit in an int, it must be a long or long 2186 // long value. ISO C does not support this, but GCC does as an extension, 2187 // emit a warning. 2188 unsigned IntWidth = Context.Target.getIntWidth(); 2189 2190 // Verify that all the values are okay, compute the size of the values, and 2191 // reverse the list. 2192 unsigned NumNegativeBits = 0; 2193 unsigned NumPositiveBits = 0; 2194 2195 // Keep track of whether all elements have type int. 2196 bool AllElementsInt = true; 2197 2198 EnumConstantDecl *EltList = 0; 2199 for (unsigned i = 0; i != NumElements; ++i) { 2200 EnumConstantDecl *ECD = 2201 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2202 if (!ECD) continue; // Already issued a diagnostic. 2203 2204 // If the enum value doesn't fit in an int, emit an extension warning. 2205 const llvm::APSInt &InitVal = ECD->getInitVal(); 2206 assert(InitVal.getBitWidth() >= IntWidth && 2207 "Should have promoted value to int"); 2208 if (InitVal.getBitWidth() > IntWidth) { 2209 llvm::APSInt V(InitVal); 2210 V.trunc(IntWidth); 2211 V.extend(InitVal.getBitWidth()); 2212 if (V != InitVal) 2213 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2214 InitVal.toString()); 2215 } 2216 2217 // Keep track of the size of positive and negative values. 2218 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2219 NumPositiveBits = std::max(NumPositiveBits, 2220 (unsigned)InitVal.getActiveBits()); 2221 else 2222 NumNegativeBits = std::max(NumNegativeBits, 2223 (unsigned)InitVal.getMinSignedBits()); 2224 2225 // Keep track of whether every enum element has type int (very commmon). 2226 if (AllElementsInt) 2227 AllElementsInt = ECD->getType() == Context.IntTy; 2228 2229 ECD->setNextDeclarator(EltList); 2230 EltList = ECD; 2231 } 2232 2233 // Figure out the type that should be used for this enum. 2234 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2235 QualType BestType; 2236 unsigned BestWidth; 2237 2238 if (NumNegativeBits) { 2239 // If there is a negative value, figure out the smallest integer type (of 2240 // int/long/longlong) that fits. 2241 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2242 BestType = Context.IntTy; 2243 BestWidth = IntWidth; 2244 } else { 2245 BestWidth = Context.Target.getLongWidth(); 2246 2247 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2248 BestType = Context.LongTy; 2249 else { 2250 BestWidth = Context.Target.getLongLongWidth(); 2251 2252 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2253 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2254 BestType = Context.LongLongTy; 2255 } 2256 } 2257 } else { 2258 // If there is no negative value, figure out which of uint, ulong, ulonglong 2259 // fits. 2260 if (NumPositiveBits <= IntWidth) { 2261 BestType = Context.UnsignedIntTy; 2262 BestWidth = IntWidth; 2263 } else if (NumPositiveBits <= 2264 (BestWidth = Context.Target.getLongWidth())) { 2265 BestType = Context.UnsignedLongTy; 2266 } else { 2267 BestWidth = Context.Target.getLongLongWidth(); 2268 assert(NumPositiveBits <= BestWidth && 2269 "How could an initializer get larger than ULL?"); 2270 BestType = Context.UnsignedLongLongTy; 2271 } 2272 } 2273 2274 // Loop over all of the enumerator constants, changing their types to match 2275 // the type of the enum if needed. 2276 for (unsigned i = 0; i != NumElements; ++i) { 2277 EnumConstantDecl *ECD = 2278 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2279 if (!ECD) continue; // Already issued a diagnostic. 2280 2281 // Standard C says the enumerators have int type, but we allow, as an 2282 // extension, the enumerators to be larger than int size. If each 2283 // enumerator value fits in an int, type it as an int, otherwise type it the 2284 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2285 // that X has type 'int', not 'unsigned'. 2286 if (ECD->getType() == Context.IntTy) { 2287 // Make sure the init value is signed. 2288 llvm::APSInt IV = ECD->getInitVal(); 2289 IV.setIsSigned(true); 2290 ECD->setInitVal(IV); 2291 continue; // Already int type. 2292 } 2293 2294 // Determine whether the value fits into an int. 2295 llvm::APSInt InitVal = ECD->getInitVal(); 2296 bool FitsInInt; 2297 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2298 FitsInInt = InitVal.getActiveBits() < IntWidth; 2299 else 2300 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2301 2302 // If it fits into an integer type, force it. Otherwise force it to match 2303 // the enum decl type. 2304 QualType NewTy; 2305 unsigned NewWidth; 2306 bool NewSign; 2307 if (FitsInInt) { 2308 NewTy = Context.IntTy; 2309 NewWidth = IntWidth; 2310 NewSign = true; 2311 } else if (ECD->getType() == BestType) { 2312 // Already the right type! 2313 continue; 2314 } else { 2315 NewTy = BestType; 2316 NewWidth = BestWidth; 2317 NewSign = BestType->isSignedIntegerType(); 2318 } 2319 2320 // Adjust the APSInt value. 2321 InitVal.extOrTrunc(NewWidth); 2322 InitVal.setIsSigned(NewSign); 2323 ECD->setInitVal(InitVal); 2324 2325 // Adjust the Expr initializer and type. 2326 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2327 ECD->setType(NewTy); 2328 } 2329 2330 Enum->defineElements(EltList, BestType); 2331 Consumer.HandleTagDeclDefinition(Enum); 2332} 2333 2334Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2335 ExprTy *expr) { 2336 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2337 2338 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2339} 2340 2341Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2342 SourceLocation LBrace, 2343 SourceLocation RBrace, 2344 const char *Lang, 2345 unsigned StrSize, 2346 DeclTy *D) { 2347 LinkageSpecDecl::LanguageIDs Language; 2348 Decl *dcl = static_cast<Decl *>(D); 2349 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2350 Language = LinkageSpecDecl::lang_c; 2351 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2352 Language = LinkageSpecDecl::lang_cxx; 2353 else { 2354 Diag(Loc, diag::err_bad_language); 2355 return 0; 2356 } 2357 2358 // FIXME: Add all the various semantics of linkage specifications 2359 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2360} 2361 2362void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { 2363 2364 switch (Attr->getKind()) { 2365 case AttributeList::AT_vector_size: 2366 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2367 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 2368 if (!newType.isNull()) // install the new vector type into the decl 2369 vDecl->setType(newType); 2370 } 2371 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2372 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 2373 Attr); 2374 if (!newType.isNull()) // install the new vector type into the decl 2375 tDecl->setUnderlyingType(newType); 2376 } 2377 break; 2378 case AttributeList::AT_ext_vector_type: 2379 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 2380 HandleExtVectorTypeAttribute(tDecl, Attr); 2381 else 2382 Diag(Attr->getLoc(), 2383 diag::err_typecheck_ext_vector_not_typedef); 2384 break; 2385 case AttributeList::AT_address_space: 2386 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2387 QualType newType = HandleAddressSpaceTypeAttribute( 2388 tDecl->getUnderlyingType(), 2389 Attr); 2390 tDecl->setUnderlyingType(newType); 2391 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2392 QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), 2393 Attr); 2394 // install the new addr spaced type into the decl 2395 vDecl->setType(newType); 2396 } 2397 break; 2398 case AttributeList::AT_mode: 2399 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2400 QualType newType = HandleModeTypeAttribute(tDecl->getUnderlyingType(), 2401 Attr); 2402 tDecl->setUnderlyingType(newType); 2403 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2404 QualType newType = HandleModeTypeAttribute(vDecl->getType(), Attr); 2405 vDecl->setType(newType); 2406 } 2407 // FIXME: Diagnostic? 2408 break; 2409 case AttributeList::AT_deprecated: 2410 HandleDeprecatedAttribute(New, Attr); 2411 break; 2412 case AttributeList::AT_visibility: 2413 HandleVisibilityAttribute(New, Attr); 2414 break; 2415 case AttributeList::AT_weak: 2416 HandleWeakAttribute(New, Attr); 2417 break; 2418 case AttributeList::AT_dllimport: 2419 HandleDLLImportAttribute(New, Attr); 2420 break; 2421 case AttributeList::AT_dllexport: 2422 HandleDLLExportAttribute(New, Attr); 2423 break; 2424 case AttributeList::AT_nothrow: 2425 HandleNothrowAttribute(New, Attr); 2426 break; 2427 case AttributeList::AT_stdcall: 2428 HandleStdCallAttribute(New, Attr); 2429 break; 2430 case AttributeList::AT_fastcall: 2431 HandleFastCallAttribute(New, Attr); 2432 break; 2433 case AttributeList::AT_aligned: 2434 HandleAlignedAttribute(New, Attr); 2435 break; 2436 case AttributeList::AT_packed: 2437 HandlePackedAttribute(New, Attr); 2438 break; 2439 case AttributeList::AT_annotate: 2440 HandleAnnotateAttribute(New, Attr); 2441 break; 2442 case AttributeList::AT_noreturn: 2443 HandleNoReturnAttribute(New, Attr); 2444 break; 2445 case AttributeList::AT_format: 2446 HandleFormatAttribute(New, Attr); 2447 break; 2448 case AttributeList::AT_transparent_union: 2449 HandleTransparentUnionAttribute(New, Attr); 2450 break; 2451 default: 2452#if 0 2453 // TODO: when we have the full set of attributes, warn about unknown ones. 2454 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 2455 Attr->getName()->getName()); 2456#endif 2457 break; 2458 } 2459} 2460 2461void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, 2462 AttributeList *declarator_postfix) { 2463 while (declspec_prefix) { 2464 HandleDeclAttribute(New, declspec_prefix); 2465 declspec_prefix = declspec_prefix->getNext(); 2466 } 2467 while (declarator_postfix) { 2468 HandleDeclAttribute(New, declarator_postfix); 2469 declarator_postfix = declarator_postfix->getNext(); 2470 } 2471} 2472 2473void Sema::HandleExtVectorTypeAttribute(TypedefDecl *tDecl, 2474 AttributeList *rawAttr) { 2475 QualType curType = tDecl->getUnderlyingType(); 2476 // check the attribute arguments. 2477 if (rawAttr->getNumArgs() != 1) { 2478 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2479 std::string("1")); 2480 return; 2481 } 2482 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2483 llvm::APSInt vecSize(32); 2484 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2485 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2486 "ext_vector_type", sizeExpr->getSourceRange()); 2487 return; 2488 } 2489 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2490 // in conjunction with complex types (pointers, arrays, functions, etc.). 2491 Type *canonType = curType.getCanonicalType().getTypePtr(); 2492 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2493 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2494 curType.getCanonicalType().getAsString()); 2495 return; 2496 } 2497 // unlike gcc's vector_size attribute, the size is specified as the 2498 // number of elements, not the number of bytes. 2499 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2500 2501 if (vectorSize == 0) { 2502 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2503 sizeExpr->getSourceRange()); 2504 return; 2505 } 2506 // Instantiate/Install the vector type, the number of elements is > 0. 2507 tDecl->setUnderlyingType(Context.getExtVectorType(curType, vectorSize)); 2508 // Remember this typedef decl, we will need it later for diagnostics. 2509 ExtVectorDecls.push_back(tDecl); 2510} 2511 2512QualType Sema::HandleVectorTypeAttribute(QualType curType, 2513 AttributeList *rawAttr) { 2514 // check the attribute arugments. 2515 if (rawAttr->getNumArgs() != 1) { 2516 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2517 std::string("1")); 2518 return QualType(); 2519 } 2520 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2521 llvm::APSInt vecSize(32); 2522 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2523 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2524 "vector_size", sizeExpr->getSourceRange()); 2525 return QualType(); 2526 } 2527 // navigate to the base type - we need to provide for vector pointers, 2528 // vector arrays, and functions returning vectors. 2529 Type *canonType = curType.getCanonicalType().getTypePtr(); 2530 2531 if (canonType->isPointerType() || canonType->isArrayType() || 2532 canonType->isFunctionType()) { 2533 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2534 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2535 do { 2536 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2537 canonType = PT->getPointeeType().getTypePtr(); 2538 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2539 canonType = AT->getElementType().getTypePtr(); 2540 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2541 canonType = FT->getResultType().getTypePtr(); 2542 } while (canonType->isPointerType() || canonType->isArrayType() || 2543 canonType->isFunctionType()); 2544 */ 2545 } 2546 // the base type must be integer or float. 2547 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2548 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2549 curType.getCanonicalType().getAsString()); 2550 return QualType(); 2551 } 2552 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2553 // vecSize is specified in bytes - convert to bits. 2554 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2555 2556 // the vector size needs to be an integral multiple of the type size. 2557 if (vectorSize % typeSize) { 2558 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2559 sizeExpr->getSourceRange()); 2560 return QualType(); 2561 } 2562 if (vectorSize == 0) { 2563 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2564 sizeExpr->getSourceRange()); 2565 return QualType(); 2566 } 2567 // Instantiate the vector type, the number of elements is > 0, and not 2568 // required to be a power of 2, unlike GCC. 2569 return Context.getVectorType(curType, vectorSize/typeSize); 2570} 2571 2572void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { 2573 // check the attribute arguments. 2574 if (rawAttr->getNumArgs() > 0) { 2575 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2576 std::string("0")); 2577 return; 2578 } 2579 2580 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2581 TD->addAttr(new PackedAttr); 2582 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2583 // If the alignment is less than or equal to 8 bits, the packed attribute 2584 // has no effect. 2585 if (!FD->getType()->isIncompleteType() && 2586 Context.getTypeAlign(FD->getType()) <= 8) 2587 Diag(rawAttr->getLoc(), 2588 diag::warn_attribute_ignored_for_field_of_type, 2589 rawAttr->getName()->getName(), FD->getType().getAsString()); 2590 else 2591 FD->addAttr(new PackedAttr); 2592 } else 2593 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2594 rawAttr->getName()->getName()); 2595} 2596 2597void Sema::HandleNoReturnAttribute(Decl *d, AttributeList *rawAttr) { 2598 // check the attribute arguments. 2599 if (rawAttr->getNumArgs() != 0) { 2600 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2601 std::string("0")); 2602 return; 2603 } 2604 2605 FunctionDecl *Fn = dyn_cast<FunctionDecl>(d); 2606 2607 if (!Fn) { 2608 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2609 "noreturn", "function"); 2610 return; 2611 } 2612 2613 d->addAttr(new NoReturnAttr()); 2614} 2615 2616void Sema::HandleDeprecatedAttribute(Decl *d, AttributeList *rawAttr) { 2617 // check the attribute arguments. 2618 if (rawAttr->getNumArgs() != 0) { 2619 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2620 std::string("0")); 2621 return; 2622 } 2623 2624 d->addAttr(new DeprecatedAttr()); 2625} 2626 2627void Sema::HandleVisibilityAttribute(Decl *d, AttributeList *rawAttr) { 2628 // check the attribute arguments. 2629 if (rawAttr->getNumArgs() != 1) { 2630 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2631 std::string("1")); 2632 return; 2633 } 2634 2635 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2636 Arg = Arg->IgnoreParenCasts(); 2637 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2638 2639 if (Str == 0 || Str->isWide()) { 2640 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2641 "visibility", std::string("1")); 2642 return; 2643 } 2644 2645 const char *TypeStr = Str->getStrData(); 2646 unsigned TypeLen = Str->getByteLength(); 2647 VisibilityAttr::VisibilityTypes type; 2648 2649 if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) 2650 type = VisibilityAttr::DefaultVisibility; 2651 else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) 2652 type = VisibilityAttr::HiddenVisibility; 2653 else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) 2654 type = VisibilityAttr::HiddenVisibility; // FIXME 2655 else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) 2656 type = VisibilityAttr::ProtectedVisibility; 2657 else { 2658 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2659 "visibility", TypeStr); 2660 return; 2661 } 2662 2663 d->addAttr(new VisibilityAttr(type)); 2664} 2665 2666void Sema::HandleWeakAttribute(Decl *d, AttributeList *rawAttr) { 2667 // check the attribute arguments. 2668 if (rawAttr->getNumArgs() != 0) { 2669 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2670 std::string("0")); 2671 return; 2672 } 2673 2674 d->addAttr(new WeakAttr()); 2675} 2676 2677void Sema::HandleDLLImportAttribute(Decl *d, AttributeList *rawAttr) { 2678 // check the attribute arguments. 2679 if (rawAttr->getNumArgs() != 0) { 2680 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2681 std::string("0")); 2682 return; 2683 } 2684 2685 d->addAttr(new DLLImportAttr()); 2686} 2687 2688void Sema::HandleDLLExportAttribute(Decl *d, AttributeList *rawAttr) { 2689 // check the attribute arguments. 2690 if (rawAttr->getNumArgs() != 0) { 2691 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2692 std::string("0")); 2693 return; 2694 } 2695 2696 d->addAttr(new DLLExportAttr()); 2697} 2698 2699void Sema::HandleStdCallAttribute(Decl *d, AttributeList *rawAttr) { 2700 // check the attribute arguments. 2701 if (rawAttr->getNumArgs() != 0) { 2702 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2703 std::string("0")); 2704 return; 2705 } 2706 2707 d->addAttr(new StdCallAttr()); 2708} 2709 2710void Sema::HandleFastCallAttribute(Decl *d, AttributeList *rawAttr) { 2711 // check the attribute arguments. 2712 if (rawAttr->getNumArgs() != 0) { 2713 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2714 std::string("0")); 2715 return; 2716 } 2717 2718 d->addAttr(new FastCallAttr()); 2719} 2720 2721void Sema::HandleNothrowAttribute(Decl *d, AttributeList *rawAttr) { 2722 // check the attribute arguments. 2723 if (rawAttr->getNumArgs() != 0) { 2724 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2725 std::string("0")); 2726 return; 2727 } 2728 2729 d->addAttr(new NoThrowAttr()); 2730} 2731 2732static const FunctionTypeProto *getFunctionProto(Decl *d) { 2733 QualType Ty; 2734 2735 if (ValueDecl *decl = dyn_cast<ValueDecl>(d)) 2736 Ty = decl->getType(); 2737 else if (FieldDecl *decl = dyn_cast<FieldDecl>(d)) 2738 Ty = decl->getType(); 2739 else if (TypedefDecl* decl = dyn_cast<TypedefDecl>(d)) 2740 Ty = decl->getUnderlyingType(); 2741 else 2742 return 0; 2743 2744 if (Ty->isFunctionPointerType()) { 2745 const PointerType *PtrTy = Ty->getAsPointerType(); 2746 Ty = PtrTy->getPointeeType(); 2747 } 2748 2749 if (const FunctionType *FnTy = Ty->getAsFunctionType()) 2750 return dyn_cast<FunctionTypeProto>(FnTy->getAsFunctionType()); 2751 2752 return 0; 2753} 2754 2755static inline bool isNSStringType(QualType T, ASTContext &Ctx) { 2756 if (!T->isPointerType()) 2757 return false; 2758 2759 T = T->getAsPointerType()->getPointeeType().getCanonicalType(); 2760 ObjCInterfaceType* ClsT = dyn_cast<ObjCInterfaceType>(T.getTypePtr()); 2761 2762 if (!ClsT) 2763 return false; 2764 2765 IdentifierInfo* ClsName = ClsT->getDecl()->getIdentifier(); 2766 2767 // FIXME: Should we walk the chain of classes? 2768 return ClsName == &Ctx.Idents.get("NSString") || 2769 ClsName == &Ctx.Idents.get("NSMutableString"); 2770} 2771 2772/// Handle __attribute__((format(type,idx,firstarg))) attributes 2773/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html 2774void Sema::HandleFormatAttribute(Decl *d, AttributeList *rawAttr) { 2775 2776 if (!rawAttr->getParameterName()) { 2777 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2778 "format", std::string("1")); 2779 return; 2780 } 2781 2782 if (rawAttr->getNumArgs() != 2) { 2783 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2784 std::string("3")); 2785 return; 2786 } 2787 2788 // GCC ignores the format attribute on K&R style function 2789 // prototypes, so we ignore it as well 2790 const FunctionTypeProto *proto = getFunctionProto(d); 2791 2792 if (!proto) { 2793 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2794 "format", "function"); 2795 return; 2796 } 2797 2798 // FIXME: in C++ the implicit 'this' function parameter also counts. 2799 // this is needed in order to be compatible with GCC 2800 // the index must start in 1 and the limit is numargs+1 2801 unsigned NumArgs = proto->getNumArgs(); 2802 unsigned FirstIdx = 1; 2803 2804 const char *Format = rawAttr->getParameterName()->getName(); 2805 unsigned FormatLen = rawAttr->getParameterName()->getLength(); 2806 2807 // Normalize the argument, __foo__ becomes foo. 2808 if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && 2809 Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { 2810 Format += 2; 2811 FormatLen -= 4; 2812 } 2813 2814 bool Supported = false; 2815 bool is_NSString = false; 2816 bool is_strftime = false; 2817 2818 switch (FormatLen) { 2819 default: break; 2820 case 5: 2821 Supported = !memcmp(Format, "scanf", 5); 2822 break; 2823 case 6: 2824 Supported = !memcmp(Format, "printf", 6); 2825 break; 2826 case 7: 2827 Supported = !memcmp(Format, "strfmon", 7); 2828 break; 2829 case 8: 2830 Supported = (is_strftime = !memcmp(Format, "strftime", 8)) || 2831 (is_NSString = !memcmp(Format, "NSString", 8)); 2832 break; 2833 } 2834 2835 if (!Supported) { 2836 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2837 "format", rawAttr->getParameterName()->getName()); 2838 return; 2839 } 2840 2841 // checks for the 2nd argument 2842 Expr *IdxExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2843 llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); 2844 if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { 2845 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2846 "format", std::string("2"), IdxExpr->getSourceRange()); 2847 return; 2848 } 2849 2850 if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { 2851 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2852 "format", std::string("2"), IdxExpr->getSourceRange()); 2853 return; 2854 } 2855 2856 // FIXME: Do we need to bounds check? 2857 unsigned ArgIdx = Idx.getZExtValue() - 1; 2858 2859 // make sure the format string is really a string 2860 QualType Ty = proto->getArgType(ArgIdx); 2861 2862 if (is_NSString) { 2863 // FIXME: do we need to check if the type is NSString*? What are 2864 // the semantics? 2865 if (!isNSStringType(Ty, Context)) { 2866 // FIXME: Should highlight the actual expression that has the 2867 // wrong type. 2868 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_NSString, 2869 IdxExpr->getSourceRange()); 2870 return; 2871 } 2872 } 2873 else if (!Ty->isPointerType() || 2874 !Ty->getAsPointerType()->getPointeeType()->isCharType()) { 2875 // FIXME: Should highlight the actual expression that has the 2876 // wrong type. 2877 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, 2878 IdxExpr->getSourceRange()); 2879 return; 2880 } 2881 2882 // check the 3rd argument 2883 Expr *FirstArgExpr = static_cast<Expr *>(rawAttr->getArg(1)); 2884 llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); 2885 if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { 2886 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2887 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2888 return; 2889 } 2890 2891 // check if the function is variadic if the 3rd argument non-zero 2892 if (FirstArg != 0) { 2893 if (proto->isVariadic()) { 2894 ++NumArgs; // +1 for ... 2895 } else { 2896 Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); 2897 return; 2898 } 2899 } 2900 2901 // strftime requires FirstArg to be 0 because it doesn't read from any variable 2902 // the input is just the current time + the format string 2903 if (is_strftime) { 2904 if (FirstArg != 0) { 2905 Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, 2906 FirstArgExpr->getSourceRange()); 2907 return; 2908 } 2909 // if 0 it disables parameter checking (to use with e.g. va_list) 2910 } else if (FirstArg != 0 && FirstArg != NumArgs) { 2911 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2912 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2913 return; 2914 } 2915 2916 d->addAttr(new FormatAttr(std::string(Format, FormatLen), 2917 Idx.getZExtValue(), FirstArg.getZExtValue())); 2918} 2919 2920void Sema::HandleTransparentUnionAttribute(Decl *d, AttributeList *rawAttr) { 2921 // check the attribute arguments. 2922 if (rawAttr->getNumArgs() != 0) { 2923 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2924 std::string("0")); 2925 return; 2926 } 2927 2928 TypeDecl *decl = dyn_cast<TypeDecl>(d); 2929 2930 if (!decl || !Context.getTypeDeclType(decl)->isUnionType()) { 2931 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2932 "transparent_union", "union"); 2933 return; 2934 } 2935 2936 //QualType QTy = Context.getTypeDeclType(decl); 2937 //const RecordType *Ty = QTy->getAsUnionType(); 2938 2939// FIXME 2940// Ty->addAttr(new TransparentUnionAttr()); 2941} 2942 2943void Sema::HandleAnnotateAttribute(Decl *d, AttributeList *rawAttr) { 2944 // check the attribute arguments. 2945 if (rawAttr->getNumArgs() != 1) { 2946 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2947 std::string("1")); 2948 return; 2949 } 2950 Expr *argExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2951 StringLiteral *SE = dyn_cast<StringLiteral>(argExpr); 2952 2953 // Make sure that there is a string literal as the annotation's single 2954 // argument. 2955 if (!SE) { 2956 Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); 2957 return; 2958 } 2959 d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), 2960 SE->getByteLength()))); 2961} 2962 2963void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr) 2964{ 2965 // check the attribute arguments. 2966 if (rawAttr->getNumArgs() > 1) { 2967 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2968 std::string("1")); 2969 return; 2970 } 2971 2972 unsigned Align = 0; 2973 2974 if (rawAttr->getNumArgs() == 0) { 2975 // FIXME: This should be the target specific maximum alignment. 2976 // (For now we just use 128 bits which is the maximum on X86. 2977 Align = 128; 2978 return; 2979 } else { 2980 Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2981 llvm::APSInt alignment(32); 2982 if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { 2983 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2984 "aligned", alignmentExpr->getSourceRange()); 2985 return; 2986 } 2987 2988 Align = alignment.getZExtValue() * 8; 2989 } 2990 2991 d->addAttr(new AlignedAttr(Align)); 2992} 2993